Eragrostis unioloides (Retzius) Nees ex Steudel

Gramineae

• Poa unioloides Retzius (1789)

Common names

Indonesia: padang togu (Batak), rumput udang (Indonesian).Malaysia: ramput kolam padang. Thailand: ya-khaipu (northern).

Origin and geographic distribution

E. unioloides is native to South-East Asia. It is also found in the Indian subcontinent, Sri Lanka and the Pacific Islands.

Description

Annual or short-lived perennial grass, tufted, with culms 10-80 cm tall, erect or geniculately ascending, sometimes rooting from the lower nodes. Leaf-sheath about 1.5 cm long, striate, purplish, hairy at the mouth; ligule a fringe of hairs; leaf-blade linear with broad base and acute top, 2-20 cm x 2-8 mm, flat or inrolled. Inflorescence a loose or contracted, terminal, usually stiffly erect panicle, up to 20 cm long; spikelets 8-60-flowered, ovoid to oblongoid, 4-16 mm x 2.5-4 mm, strongly compressed, on up to 15 mm long peduncles, usually yellowish but reddish-purple tinged; lower florets all fertile, upper ones caducous, but florets falling in succession from the base up; glumes very densely packed, keel scabrid. Caryopsis obovoid to ellipsoid, laterally compressed, ca. 0.7 mm long, orange-brown. It is a very variable species, the main variation being in the annual to perennial type and in the degree of stoloniferous habit (Manidool 1992).

Use

E. unioloides is used as a forage, but not of great importance. Its abundance as a weed in irrigated rice fields (Häfliger and Scholz 1981) makes it useful for grazing after the rice harvest and as a green manure.

Properties

There is no published information on chemical composition, but its quality is likely to be low because of its low leaf/stem ratio.

Toxicity

None has been reported.

Ecology

E. unioloides can grow from sea-level up to 1250 m altitude, in open or moderately shaded areas, in swampy or paddy fields, roadsides and cultivated land.

Growth and development

Flower heads emerge 6-8 weeks after seedling emergence and plants flower throughout the year.

Performance

E. unioloides is grazed but does not withstand heavy grazing. In northern Thailand, villagers may pull up whole plants and feed them fresh to cattle.

Links

• Germplasm Resources Information Network USA: description, econonmic importance and distributional range of E. unioloides
• Atlas of Florida Vascular Plants: information and map on E. unioloides in Florida

Link for the genus

• Grass Genera of the World: very detailed description, habit, economics and references on Eragrostis

References

Häfliger E. and Scholz H. (1981); Manidool C. (1992)